Model 3585A
Performance Tests
h p 3 5 8 5 A
S P E C T R U M A N A L Y Z E R
50
o r
7 5 OHM
FEEDTHRU
FROM
SYNTHES I ZER
OUTPUT
I M
Figure 4·3. 1 M ohm Input Impedance Test
4· 1 9. Marker Accuracy
This test verifies that the 3585A meets its marker accuracy specification .
Specification:
±
0.2"70 of frequency span
±
Resolution Bandwidth Setting
Procedure:
a. Set the 3585A controls for:
INSTRUMENT PRESET
b. Set the synthesizer controls for :
FREQUENCY
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20. 8 MHz
AMPLITUDE
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
-25 dBm
c. Connect the 500 output of the synthesizer to the 500 input of the 3585A.
d . Put the marker at the peak of the response shown on the 3585A CRT.
e . The marker frequency should read between 20.00 MHz and 20. 1 6 MHz thereby verify
ing that the 3585A marker reads within
±
0.2% of the input frequency.
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